Atomic Fast: Fasting & Diet
AI Calorie & Meal Tracker
Free · In-App Purchases · Designed for iPad. Not verified for macOS.
Snap a photo of your meal to estimate calories, macros, and nutrients in seconds. Track your fasts. See how your eating patterns, hydration, sleep, and activity connect over time.
AtomicFast combines intermittent fasting, AI calorie tracking, macro counting, Apple Health insights, and hydration tracking in one app — made for people who already fast and want more than just a basic timer or food diary.
FASTING TIMER WITH METABOLIC PHASES
Track your fasts with a real-time fasting timer and estimated metabolic phase guidance. Follow your progress through clear visual stages, from digestion and transition to glycogen depletion, fat burning, deeper fasting, and autophagy. Tracking your fast is easy, zero hassle.
Choose popular fasting schedules like 16:8, 18:6, 20:4, OMAD, or create your own custom plan. Adjust your goals anytime, and get fasting milestone notifications without the pressure.
AI CALORIE TRACKING IN SECONDS
Take a photo of your plate. AtomicFast typically identifies foods in under 5 seconds and estimates calories, macros, and nutrients — like a smart AI calorie counter and macro tracker that actually understands what you ate.
You can also log meals by:
- Describing what you ate with text or voice
- Scanning nutrition labels
- Scanning barcodes
- Searching the USDA food database
- Adding meals manually when needed
No more typing one ingredient at a time just to understand what you ate.
BREAK-FAST SCORE
The first meal after a fast matters. AtomicFast scores your break-fast meal from 0 to 100, with practical suggestions on protein, fiber, carbs, and balance for a smoother transition back into eating.
MEALS AND FASTS THAT WORK TOGETHER
Most fasting apps track time. Most calorie trackers and food diaries track food. AtomicFast connects both.
See how your last meal affects your next fast, how your fasting consistency affects your eating patterns, and how nutrition timing may connect with sleep, recovery, and daily energy.
METABOLIC INSIGHTS
AtomicFast helps you spot patterns across fasting, meals, hydration, sleep, heart rate, HRV, activity, and more.
Interactive charts and daily insights help you understand habits like calorie trends, macro balance, fasting consistency, and how nutrition timing may connect with sleep, recovery, and energy levels.
Daily insight examples:
- "Ending eating by 7 PM dropped your sleeping heart rate by 4 bpm last week"
- "On high-recovery days you hit your fasting goal 30% more often"
Insights are calculated on your device. Your patterns stay yours.
DAILY READINESS SCORE
Wake up to a readiness score from key health signals: sleep, HRV, resting heart rate, activity, exercise, and respiratory rate.
A simple guide to whether today is a good day to push your fast, stay normal, or focus on recovery.
APPLE HEALTH AND APPLE WATCH
AtomicFast syncs 24 Apple Health data types: sleep, heart rate, HRV, steps, workouts, weight, respiratory rate, and more.
Meals write 11 nutrients plus water back to Apple Health, keeping your nutrition data connected across your favorite health apps.
HYDRATION TRACKING
One-tap water logging. Smart reminders that fit naturally around your fasting routine.
BUILT FOR EVERYDAY USE
- Three themes including a signature Deep Purple mode
- Two timer styles: Atomic Ring and Classic Ring
- Smart notifications for fasting milestones, hydration, meal reminders, and weekly recaps
- Awards and streaks to celebrate progress without pressure
- Offline-first experience
- Privacy-focused design
- Apple Watch companion app
ATOMIC+ SUBSCRIPTION
The free version is the real product — fasting tracking, manual food logging, readiness score, daily insights, themes, and 7 AI meal scans per week, all free and ad-free.
Atomic+ unlocks:
- Unlimited AI meal scans
- iCloud backup and data export
Available as Atomic+ Monthly, Atomic+ Annual (with 7-day free trial), or Atomic+ Lifetime.
Terms of Use: https://atomicfast.com/terms
Privacy Policy: https://atomicfast.com/privacy
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
This update fixes an important sign-in issue.
If your account ever gets stuck on a "Token refresh failed" error, the app now detects it and takes you safely back to the sign-in screen — sign in again with the same email and you're back, with your fasting history intact.
The developer, Startise, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Contact Info
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- User Content
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Size
- 19.8 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - iPad
Requires iPadOS 18.0 or later. - Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.0 or later. - Apple Watch
Requires watchOS 10.0 or later.
- iPhone
- Languages
- English
- Age Rating
9+
- 9+
- Contains
Health or Wellness Topics
- In-App Purchases
Yes
- Atomic+ Lifetime 69,99 €
- Atomic+ Annual 34,99 €
- Atomic+ Monthly 5,99 €
- Provider
Startise Limited
- Startise Limited has not identified itself as a trader for this app. If you are a consumer in the European Economic Area, consumer rights do not apply to agreements between you and the provider.
- Copyright
- © 2026 Atomic Fast